The Ethiopian Highlands is a rugged mass of mountains in Ethiopia, situated in the Horn region in Northeast Africa. It forms the largest continuous area of its altitude in the continent, with little of its surface falling below 1500 m (4,921 ft), while the summits reach heights of up to 4550 m (14,928 ft). It is sometimes called the Roof of Africa due to its height and large area.[1] Most of the Ethiopian Highlands are part of central and northern Ethiopia, and its northernmost portion reaches into Eritrea.

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In the southern parts of the Ethiopian Highlands once was located the Kingdom of Kaffa, a medieval early modern state, whence the coffee plant was exported to the Arabian peninsula. The land of the former kingdom is mountainous with stretches of forest, the land is very fertile, capable of three harvests a year. The term "coffee" derives from the Arabicqahwah ( قهوة)[2] and is traced to Kaffa.[2][3]

The Ethiopian Highlands began to rise 75 million years ago[citation needed], as magma from the Earth's mantle uplifted a broad dome of the ancient rocks of the Arabian-Nubian Shield. The opening of the Great Rift Valley split the dome of the Ethiopian Highlands into three parts; the mountains of the southern Arabian Peninsula are geologically part of the ancient Ethiopian Highlands, separated by the rifting which created the Red Sea and Gulf of Aden and separated Africa from Arabia.

Around 30 million years ago, a flood basalt plateau began to form, piling layers upon layers of voluminous fissure-fed basaltic lava flows. Most of the flows were tholeiitic, save for a thin layer of alkali basalts and minor amounts of felsic (high-silica) volcanic rocks, such as rhyolite; in the waning stages of the flood basalt episode, large explosive caldera-forming eruptions also occurred.

The Ethiopian Highlands were eventually bisected by the Great Rift Valley as the African continental crust pulled apart, this rifting gave rise to large alkaline basalt shield volcanoes beginning about 30–31 million years ago.[4]

Because the highlands elevate Ethiopia, located close to the equator, this has resulted in giving this country an unexpectedly temperate climate. Further, these mountains catch the precipitation of the monsoon winds of the Indian Ocean, resulting in a rainy season that lasts from June until mid-September.[6] These heavy rains cause the Nile to flood in the summer, a phenomenon that puzzled the ancient Greeks, as the summer is the driest season in the Mediterranean climate that they knew.

The Ethiopian Highlands share a similar flora and fauna of other mountainous regions of Africa; this distinctive flora and fauna is known as Afromontane but from the time of the last Ice Age has been populated with some Eurasian (palearctic) flora. The habitats are somewhat different on either side of the Great Rift Valley that splits the highlands.

The highlands themselves are divided into three distinct ecoregions, distinguished by elevation, the Ethiopian montane forests lie between 1,100 and 1,800 meters elevation, above the lowland grasslands and savannas and extends to areas of similar habitat in Eritrea, Sudan, and Djibouti. This woodland belt has several natural plant communities, but has mostly been heavily grazed and converted to agricultural use now. Kolla, is an open woodland found at lower elevations, and dominated by species of Terminalia, Commiphora, Boswellia, and Acacia. Weyna dega is a woodland found in moister and higher locations, dominated by the conifersAfrocarpus gracilior and Juniperus procera. The lower portion of the Harenna Forest is a distinct woodland community, with an open canopy of Warburgia ugandensis, Croton macrostachyus, and Syzygium guineese, and Afrocarpus gracilior, with wild coffee (Coffea arabica) as the dominant understory shrub. The southwesterly winds bring rainfall from May to October with moisture from the Red Sea coming in from the east year round. Fauna at these elevations includes the endemic Harwood's francolin (Francolinus harwoodi), Prince Ruspoli's turaco (Tauraco ruspolii) and yellow-throated seedeater (Serinus flavigula), along with the Djibouti francolin (Francolinus ochropectus) in the Djibouti hills that are in the same general ecoregion.[7]

The Ethiopian montane grasslands and woodlands is the largest of the highland ecoregions, occupying the area between 1800 and 3000 meters elevations. The natural vegetation was closed-canopy forest in moister areas, and grassland, bushland, and thicket in drier areas, however these hillsides have good fertile soil and are heavily populated, largely by farming communities so most of the region has been converted to agriculture with a few areas of natural vegetation remaining. Urban areas in this ecoregion include: Ethiopia's capital city and Africa's fourth largest city Addis Ababa, the Amhara Region capital Bahir Dar with its island monasteries on Lake Tana, the old walled city of Harar, the spa town of Ambo, Asella in the Arsi Zone, the trekking center of Dodola, the lakeside Debre Zeyit, the largest city in the southwest Jimma, the market town of Nekemte, and the capital of the Tigray Region, Mek'ele. Awash National Park is a site for birdwatching.

Above 3000 meters elevation lie the high Ethiopian montane moorlands, the largest afroalpine region in Africa, the montane moorlands lie above the tree line, and consist of grassland and moorland with abundant herbs and some shrubs that have adapted to the high mountain conditions. There are several endemic animal species one of which, the Ethiopian wolf (Canis simensis), is critically endangered. Other endemics include the big-headed mole-rat (Tachyoryctes macrocephalus) which is common on the Sanetti Plateau in the Bale Mountains. The mountain nyala finds its way up to the high moorlands although it is more common at lower elevations. Wintering birds include wigeon (Anas penelope), shoveler (Anas clypeata), ruff (Philomachus pugnax) and greenshank (Tringa nebularia).

1.
Semien Mountains
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The Semien Mountains, in northern Ethiopia, north east of Gondar, are part of the Ethiopian Highlands. They are a World Heritage Site and include the Semien Mountains National Park, the mountains consist of plateaus separated by valleys and rising to pinnacles. The tallest peak is Ras Dashen, other notable heights include Mounts Biuat, because of their geological origins the mountains are almost unique, with only South Africas Drakensberg having been formed in the same manner and thus appearing similar. Notable animals in the include the walia ibex, gelada. There are a few Ethiopian wolves, the Semiens are remarkable as being one of the few spots in Africa where snow regularly falls. First mentioned in the Monumentum Adulitanum of the 4th century AD, despite their ruggedness and altitude, the mountains are dotted with villages linked by tracks. Towards the end of the Zemene Mesafint, Dejazmach Wube Haile Mariam maintained his arsenal and treasury on Mount Hai

2.
Ras Dashen
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Ras Dejen is the highest mountain in Ethiopia and tenth highest mountain of Africa. Part of Simien Mountains National Park located in the Gondar, Amhara Region, it reaches an elevation of 4,550 metres. The more common form, Ras Dashen is a corruption of its Amharic name, Ras Dejen and its western counterpart is Mount Biuat, separated by the valley of the Meshaha river. In winter snow falls rarely, since the majority of yearly rainfalls in Ethiopia are in the summer, the first recorded ascent by a Eurasian was in 1841, by the French officers Ferret and Galinier. There is no evidence of earlier ascents by locals, but the summit climate and conditions are relatively hospitable. A small fort still standing at around 4,300 Meter SRTM data. Detailed trip report Africa Ultra-Prominences on Peaklist Ras Dashen Terara, Ethiopia on Peakbagger Ras Dashen on Summitpost Ras Dashen on Peakware Elevation misquotes Simien Mountains National Park

3.
World Heritage Site
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A World Heritage Site is a landmark which has been officially recognized by the United Nations, specifically by the United Nations Educational, Scientific and Cultural Organization. Sites are selected on the basis of having cultural, historical, scientific or some form of significance. UNESCO regards these sites as being important to the interests of humanity. The programme catalogues, names, and conserves sites of outstanding cultural or natural importance to the common culture, under certain conditions, listed sites can obtain funds from the World Heritage Fund. The program was founded with the Convention Concerning the Protection of the Worlds Cultural and Natural Heritage, since then,192 state parties have ratified the convention, making it one of the most adhered to international instruments. As of July 2016,1052 sites are listed,814 cultural,203 natural, in 1959, the governments of Egypt and Sudan requested UNESCO to assist their countries to protect and rescue the endangered monuments and sites. In 1960, the Director-General of UNESCO launched an appeal to the Member States for an International Campaign to Save the Monuments of Nubia, the campaign, which ended in 1980, was considered a success. The project cost $80 million, about $40 million of which was collected from 50 countries, the projects success led to other safeguarding campaigns, saving Venice and its lagoon in Italy, the ruins of Mohenjo-daro in Pakistan, and the Borobodur Temple Compounds in Indonesia. UNESCO then initiated, with the International Council on Monuments and Sites, the United States initiated the idea of cultural conservation with nature conservation. The International Union for Conservation of Nature developed similar proposals in 1968, the Convention came into force on 17 December 1975. As of June 2016, it has been ratified by 192 states, including 188 UN member states plus the Cook Islands, the Holy See, Niue, a country must first list its significant cultural and natural sites, the result is called the Tentative List. A country may not nominate sites that have not been first included on the Tentative List, next, it can place sites selected from that list into a Nomination File. The Nomination File is evaluated by the International Council on Monuments and Sites and these bodies then make their recommendations to the World Heritage Committee. There are ten selection criteria – a site must meet at least one of them to be included on the list, up to 2004, there were six criteria for cultural heritage and four criteria for natural heritage. In 2005, this was modified so there is now only one set of ten criteria. Nominated sites must be of outstanding value and meet at least one of the ten criteria. Thus, the Geneva Convention treaty promulgates, Article 53, PROTECTION OF CULTURAL OBJECTS AND OF PLACES OF WORSHIP. There are 1,052 World Heritage Sites located in 165 States Party, of these,814 are cultural,203 are natural and 35 are mixed properties

4.
Simien Mountains National Park
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Simien Mountains National Park is one of the national parks of Ethiopia. Located in the Semien Gondar Zone of the Amhara Region, its territory covers the Simien Mountains and includes Ras Dashan and it is home to a number of endangered species, including the Ethiopian wolf and the walia ibex, a wild goat found nowhere else in the world. The gelada baboon and the caracal, a cat, also occur within the Simien Mountains, more than 50 species of birds inhabit the park, including the impressive bearded vulture, or lammergeier, with its 10-foot wingspan. The park was established in 1969, having set up by Clive Nicol. It was one of the first sites to be made a World Heritage Site by UNESCO, however, due to serious population declines of some of its characteristic native species, in 1996 it was also added to the List of World Heritage in Danger

5.
Summit
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A summit is a point on a surface that is higher in elevation than all points immediately adjacent to it. Mathematically, a summit is a maximum in elevation. The topographic terms acme, apex, peak, and zenith are synonymous, the UIAA definition is that a summit is independent if it has a prominence of 30 metres or more, it is a mountain if it has a prominence of at least 300 metres. This can be summarised as follows, A pyramidal peak is an exaggerated form produced by ice erosion of a mountain top, Summit may also refer to the highest point along a line, trail, or route. In many parts of the western United States, the term refers to the highest point along a road, highway. For example, the highest point along Interstate 80 in California is referred to as Donner Summit while the highest point on Interstate 5 is Siskiyou Mountain Summit, geoid Hill List of highest mountains Maxima and minima Nadir Summit accordance Peak finder

6.
Topographic prominence
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It is a measure of the independence of a summit. A peaks key col is a point on this contour line. By convention, the prominence of Mount Everest, the Earths highest mountain, is taken to equal the elevation of its summit above sea level, if the peaks prominence is P metres, to get from the summit to any higher terrain one must descend at least P metres. Together with the convention for Mount Everest, this implies that the prominence of any island or continental highpoint is equal to its elevation above sea level, for every ridge connecting the peak to higher terrain, find the lowest point on the ridge. The key col is defined as the highest of these cols, the prominence is the difference between the elevation of the peak and the elevation of the key col. The following mental exercise may illustrate the meaning of topographic prominence, imagine you are standing at the top of a peak and imagine that an imaginary sea level rises to your feet. Now slowly lower the sea level and an imaginary island appears beneath your feet. Your island will grow and will merge with other islands that emerge, the parent peak may be either close or far from the subject peak. The summit of Mount Everest is the parent peak of Aconcagua at a distance of 17,755 km, the key col may also be close or far from the subject peak. The key col for Aconcagua is the Bering Strait at a distance of 13,655 km, the key col for the South Summit of Mount Everest is about 100 m distant. Prominence is interesting to many mountaineers because it is a measurement that is strongly correlated with the subjective significance of a summit. Peaks with low prominences are either subsidiary tops of some higher summit or relatively insignificant independent summits, peaks with high prominences tend to be the highest points around and are likely to have extraordinary views. Only summits with a sufficient degree of prominence are regarded as independent mountains, for example, the worlds second-highest mountain is K2. While Mount Everests South Summit is taller than K2, it is not considered an independent mountain because it is a subsummit of the main summit, many lists of mountains take topographic prominence as a criterion for inclusion, or cutoff. John and Anne Nuttalls The Mountains of England and Wales uses a cutoff of 15 m, in the contiguous United States, the famous list of fourteeners uses a cutoff of 300 ft /91 m. Also in the U. S.2000 feet of prominence has become a threshold that signifies that a peak has major stature. This generates lists of peaks ranked by prominence, which are different from lists ranked by elevation. Such lists tend to emphasize isolated high peaks, such as range or island high points, one advantage of a prominence-ranked list is that it needs no cutoff, since a peak with high prominence is automatically an independent peak

7.
Geologic time scale
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The table of geologic time spans, presented here, agrees with the nomenclature, dates and standard color codes set forth by the International Commission on Stratigraphy. Evidence from radiometric dating indicates that Earth is about 4.54 billion years old, the geology or deep time of Earth’s past has been organized into various units according to events which took place in each period. Older time spans, which predate the reliable record, are defined by their absolute age. Some other planets and moons within the Solar System have sufficiently rigid structures to have preserved records of their own histories, for example, Venus, Mars, dominantly fluid planets, such as the gas giants, do not preserve their history in a comparable manner. Apart from the Late Heavy Bombardment, events on other planets probably had little influence on the Earth. Construction of a scale that links the planets is, therefore, of only limited relevance to the Earths time scale. The existence, timing, and terrestrial effects of the Late Heavy Bombardment is still debated, the largest defined unit of time is the supereon, composed of eons. Eons are divided into eras, which are in turn divided into periods, epochs, the terms eonothem, erathem, system, series, and stage are used to refer to the layers of rock that correspond to these periods of geologic time in Earths history. Geologists qualify these units as early, mid, and late when referring to time, and lower, middle, for example, the lower Jurassic Series in chronostratigraphy corresponds to the early Jurassic Epoch in geochronology. The adjectives are capitalized when the subdivision is formally recognized, and lower case when not, thus early Miocene but Early Jurassic. Geologic units from the time but different parts of the world often look different and contain different fossils. For example, in North America the Lower Cambrian is called the Waucoban series that is subdivided into zones based on succession of trilobites. In East Asia and Siberia, the unit is split into Alexian, Atdabanian. A key aspect of the work of the International Commission on Stratigraphy is to reconcile this conflicting terminology, the term Anthropocene is used informally by popular culture and a growing number of scientists to describe the current epoch in which we are living. The term was coined by Paul Crutzen and Eugene Stoermer in 2000 to describe the current time, others say that humans have not even started to leave their biggest impact on Earth, and therefore the Anthropocene hasnt even started yet. Whatever the case, the ICS has not officially approved the term, leonardo da Vinci concurred with Aristotles interpretation that fossils represented the remains of ancient life. The 11th-century Persian geologist Avicenna and the 13th-century Dominican bishop Albertus Magnus extended Aristotles explanation into a theory of a petrifying fluid. Avicenna also first proposed one of the principles underlying geologic time scales, the Chinese naturalist Shen Kuo also recognized the concept of deep time

8.
Mountain range
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A mountain range is a geographic area containing numerous geologically related mountains. A mountain system or system of ranges, sometimes is used to combine several geological features that are geographically related. Mountain ranges are usually segmented by highlands or mountain passes and valleys, individual mountains within the same mountain range do not necessarily have the same geologic structure or petrology. They may be a mix of different orogenic expressions and terranes, for example thrust sheets, uplifted blocks, fold mountains, most geologically young mountain ranges on the Earths land surface are associated with either the Pacific Ring of Fire or the Alpide Belt. The Andes is 7,000 kilometres long and is considered the worlds longest mountain system. The Alpide belt includes Indonesia and southeast Asia, through the Himalaya, the belt also includes other European and Asian mountain ranges. The Himalayas contain the highest mountains in the world, including Mount Everest, mountain ranges outside of these two systems include the Arctic Cordillera, the Urals, the Appalachians, the Scandinavian Mountains, the Altai Mountains and the Hijaz Mountains. If the definition of a range is stretched to include underwater mountains. The mountain systems of the earth are characterized by a tree structure, the sub-range relationship is often expressed as a parent-child relationship. For example, the White Mountains of New Hampshire and the Blue Ridge Mountains are sub-ranges of the Appalachian Mountains, equivalently, the Appalachians are the parent of the White Mountains and Blue Ridge Mountains, and the White Mountains and the Blue Ridge Mountains are children of the Appalachians. The position of mountains influences climate, such as rain or snow, when air masses move up and over mountains, the air cools producing orographic precipitation. As the air descends on the side, it warms again and is drier. Often, a shadow will affect the leeward side of a range. Mountain ranges are constantly subjected to forces which work to tear them down. Erosion is at work while the mountains are being uplifted and long after until the mountains are reduced to low hills, rivers are traditionally believed to be the principle erosive factor on mountain ranges, with their ability of bedrock incision and sediment transport. The rugged topography of a range is the product of erosion. The basins adjacent to a mountain range are filled with sediments which are buried and turned into sedimentary rock. The early Cenozoic uplift of the Rocky Mountains of Colorado provides an example and this mass of rock was removed as the range was actively undergoing uplift

9.
Mountain
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A mountain is a large landform that stretches above the surrounding land in a limited area, usually in the form of a peak. A mountain is steeper than a hill. Mountains are formed through tectonic forces or volcanism and these forces can locally raise the surface of the earth. Mountains erode slowly through the action of rivers, weather conditions, a few mountains are isolated summits, but most occur in huge mountain ranges. High elevations on mountains produce colder climates than at sea level and these colder climates strongly affect the ecosystems of mountains, different elevations have different plants and animals. Because of the less hospitable terrain and climate, mountains tend to be used less for agriculture and more for resource extraction and recreation, the highest mountain on Earth is Mount Everest in the Himalayas of Asia, whose summit is 8,850 m above mean sea level. The highest known mountain on any planet in the Solar System is Olympus Mons on Mars at 21,171 m, there is no universally accepted definition of a mountain. Elevation, volume, relief, steepness, spacing and continuity have been used as criteria for defining a mountain, whether a landform is called a mountain may depend on local usage. The highest point in San Francisco, California, is called Mount Davidson, notwithstanding its height of 300 m, similarly, Mount Scott outside Lawton, Oklahoma is only 251 m from its base to its highest point. Whittows Dictionary of Physical Geography states Some authorities regard eminences above 600 metres as mountains, in addition, some definitions also include a topographical prominence requirement, typically 100 or 500 feet. For a while, the US defined a mountain as being 1,000 feet or taller, any similar landform lower than this height was considered a hill. However, today, the United States Geological Survey concludes that these terms do not have technical definitions in the US, using these definitions, mountains cover 33% of Eurasia, 19% of South America, 24% of North America, and 14% of Africa. As a whole, 24% of the Earths land mass is mountainous, there are three main types of mountains, volcanic, fold, and block. All three types are formed from plate tectonics, when portions of the Earths crust move, crumple, compressional forces, isostatic uplift and intrusion of igneous matter forces surface rock upward, creating a landform higher than the surrounding features. The height of the feature makes it either a hill or, if higher and steeper, major mountains tend to occur in long linear arcs, indicating tectonic plate boundaries and activity. Volcanoes are formed when a plate is pushed below another plate, at a depth of around 100 km, melting occurs in rock above the slab, and forms magma that reaches the surface. When the magma reaches the surface, it builds a volcanic mountain. Examples of volcanoes include Mount Fuji in Japan and Mount Pinatubo in the Philippines, the magma does not have to reach the surface in order to create a mountain, magma that solidifies below ground can still form dome mountains, such as Navajo Mountain in the US

10.
Ethiopia
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Ethiopia, officially the Federal Democratic Republic of Ethiopia, is a country located in the Horn of Africa. It shares borders with Eritrea to the north and northeast, Djibouti and Somalia to the east, Sudan and South Sudan to the west, and Kenya to the south. With nearly 100 million inhabitants, Ethiopia is the most populous landlocked country in the world and it occupies a total area of 1,100,000 square kilometres, and its capital and largest city is Addis Ababa. Some of the oldest evidence for modern humans has been found in Ethiopia. It is widely considered as the region from modern humans first set out for the Middle East. According to linguists, the first Afroasiatic-speaking populations settled in the Horn region during the ensuing Neolithic era, tracing its roots to the 2nd millennium BC, Ethiopia was a monarchy for most of its history. During the first centuries AD, the Kingdom of Aksum maintained a unified civilization in the region, subsequently, many African nations adopted the colors of Ethiopias flag following their independence. It was the first independent African member of the 20th-century League of Nations, Ethiopias ancient Geez script, also known as Ethiopic, is one of the oldest alphabets still in use in the world. The Ethiopian calendar, which is seven years and three months behind the Gregorian calendar, co-exists alongside the Borana calendar. A slight majority of the population adheres to Christianity, while around a third follows Islam, the country is the site of the Migration to Abyssinia and the oldest Muslim settlement in Africa at Negash. A substantial population of Ethiopian Jews, known as Bete Israel, resided in Ethiopia until the 1980s, Ethiopia is a multilingual nation with around 80 ethnolinguistic groups, the four largest of which are the Oromiffa, Amhara, Somali, and Tigrayans. Most people in the country speak Afroasiatic languages of the Cushitic or Semitic branches, additionally, Omotic languages are spoken by ethnic minority groups inhabiting the southern regions. Nilo-Saharan languages are spoken by the nations Nilotic ethnic minorities. Ethiopia is the place of origin for the coffee bean which originated from the place called Kefa and it is a land of natural contrasts, with its vast fertile West, jungles, and numerous rivers, and the worlds hottest settlement of Dallol in its north. The Ethiopian Highlands are Africas largest continuous mountain ranges, and Sof Omar Caves contain Africas largest cave, Ethiopia has the most UNESCO World Heritage Sites in Africa. Ethiopia is one of the members of the UN, the Group of 24, the Non-Aligned Movement, G-77. In the 1970s and 1980s, Ethiopia suffered from civil wars, the country has begun to recover recently however, and now has the largest economy in East Africa and Central Africa. According to Global Fire Power, Ethiopia has the 42nd most powerful military in the world, the origin of the word Ethiopia is uncertain

11.
Horn of Africa
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The Horn of Africa is a peninsula in Northeast Africa. It juts hundreds of kilometers into the Arabian Sea and Indian Ocean, the area is the easternmost projection of the African continent. The Horn of Africa denotes the region containing the countries of Djibouti, Eritrea, Ethiopia and it covers approximately 2,000,000 km2 and is inhabited by roughly 115 million people. Regional studies on the Horn of Africa are carried out, among others, shell middens 125,000 years old have been found in Eritrea, indicating the diet of early humans included seafood obtained by beachcombing. According to both genetic and fossil evidence, archaic Homo sapiens evolved to modern humans solely in Africa between 200,000 and 100,000 years ago. Evidence to support the theory that recent modern humans originated in East Africa is not conclusive, today at the Bab-el-Mandeb straits, the Red Sea is about 12 miles wide, but 50,000 years ago it was much narrower and sea levels were 70 meters lower. Though the straits were never closed, there may have been islands in between which could be reached using simple rafts. It has been estimated that from a population of 2,000 to 5,000 individuals in Africa, according to linguists, the first Afro-Asiatic-speaking populations arrived in the region during the ensuing Neolithic era from the familys proposed urheimat in the Nile Valley, or the Near East. Other scholars propose that the Afro-Asiatic family developed in situ in the Horn, genetic analysis also indicates that, beginning in the pre-agricultural period, settlers from the Near East founded communities in Northeast Africa. These early settlements eventually gave rise to the Afro-Asiatic-speaking populations in the Horn, dʿmt was a kingdom located in Eritrea and northern Ethiopia, which existed during the 8th and 7th centuries BCE. With its capital at Yeha, the kingdom developed irrigation schemes, used plows, grew millet, the Kingdom of Aksum was an ancient state located in the highlands of present-day Ethiopia and Eritrea, which thrived between the 1st and 7th centuries CE. A major player in the commerce between the Roman Empire and Ancient India, Aksums rulers facilitated trade by minting their own currency. Under Ezana, the kingdom of Aksum became the first major empire to adopt Christianity, northern Somalia was an important link in the Horn, connecting the regions commerce with the rest of the ancient world. Somali sailors and merchants were the suppliers of frankincense, myrrh and spices. The Romans consequently began to refer to the region as Regio Aromatica, in the classical era, several flourishing Somali city-states such as Opone, Mosylon and Malao also competed with the Sabaeans, Parthians and Axumites for the rich Indo-Greco-Roman trade. The city of Mogadishu came to be known as the City of Islam, the Sultanate of Showa, established in 896, was one of the oldest local Muslim states. It was centered in the former Shewa province in central Ethiopia, the polity was succeeded by the Sultanate of Ifat around 1285. Ifat was governed from its capital at Zeila in northern Somalia and was the easternmost district of the former Shewa Sultanate, the Adal Sultanate was a medieval multi-ethnic Muslim state centered in the Horn region

12.
Eritrean Highlands
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The Eritrean Highlands are a mountainous region in central Eritrea that are bordered to the south by the Mareb River. It is a continuation of the Ethiopian Highlands to the south, the region has seen tremendous deforestation since the colonial period, which began in the late 19th century. The Highlands are at risk of deforestation and associated soil erosion. Furthermore, the region, lying south of the Sahel are at risk of desertification. The Highlands experience, as most tropical regions, two seasons, the season is from June-September while the dry season is from September to June. The average temperature for Asmara, which is 2,340 m above sea level is approximately 16°C, the Eritrean Highlands are drained by four major rivers towards Sudan and by several smaller rivers into the Red Sea coast of Eritrea. Flowing towards Sudan and the Nile River are the Gash and Setit Rivers, while towards Sudan without reaching the Nile are the Barka, the Eastern Escarpment of Eritrea is drained by numerous small streams. The highest point in Eritrea is located in the Eritrean Highlands at Emba Soira 116 m above sea level, the eastern edge of the Highlands falls off dramatically towards the Red Sea which causes two climatic systems to overlap. This region is oft noted for its perennial forest cover and this is also the region that Eritreas Merara coffee is grown. The soil conditions in the Eritrean Highlands is also quite complex, the predominant soils are chromic, eutric, and calsic cambisols of strong red colour. Other soils found in the highlands are lithosols, xerosols and fluvisols, environmental issues in Eritrea Geography of Eritrea

13.
Kingdom of Kaffa
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The Kingdom of Kaffa was an early modern state located in what is now Ethiopia, with its first capital at Bonga. The native language, also known as Kaffa, is one of the Omotic group of languages, the Manjo even had their own king, appointed by the King of Kaffa, and were given the duties of guarding the royal compounds and the gates of the kingdom. The kingdom was overrun and conquered in 1897, and was annexed by Ethiopia. The land where this former kingdom lay is in the parts of the Ethiopian Highlands with stretches of forest. The mountainous land is fertile, capable of three harvests a year. The Kingdom of Kaffa was founded c.1390 by Minjo, however, his informants told Amnon Orent, no one remembers the name of a single one. The first capital Bonga was either founded or captured by Bon-noghe, it was replaced by Anderaccha. During the 16th century, all of the north of the Gojeb River were lost to the Oromo migrations. Also in the later 16th century, the Emperor of Ethiopia Sarsa Dengel convinced the kingdom to officially accept Christianity as its state religion. As a result, the church of St. George was dedicated at Baha, beginning with Gali Ginocho, the kings of Kaffa began to expand the borders of their kingdom, annexing the neighboring small Gimira states of She, Benesho and Majango. It was during the reign of King Hoti Gaocho, that the territory of the Kaffa kings reached its maximum. According to Orent, the traditions of the Kaffa people relate that he ruled far and wide, conquering wherever he went, Kaffa was then held as a fief by Wolde Giyogis until 1914. The inhabitants suffered greatly from slave-raiding during the de facto rule of Lij Iyasu, during the reorganization of the provinces in 1942, the former kingdom was enlarged by the addition of a number of other kingdoms from the Gibe region to become Kaffa Province. In Kaffa, Maria Theresa Thalers and salt blocks called amoleh were used as currency as late as 1905, the economy was based on exports of gold, civet oil, and slaves. Crops raised included coffee and cotton, however, according to Richard Pankhurst, the amount of coffee exported was never large, he cites an estimate for its production in the 1880s at 50,000 to 60,000 kilograms a year. Livestock was raised, and honeybees kept in barrels which were hung in trees, werner Lange, History of the Southern Gonga

14.
Early modern period
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The early modern period of modern history follows the late Middle Ages of the post-classical era. Historians in recent decades have argued that from a worldwide standpoint, the period witnessed the exploration and colonization of the Americas and the rise of sustained contacts between previously isolated parts of the globe. The historical powers became involved in trade, as the exchange of goods, plants, animals, and food crops extended to the Old World. The Columbian Exchange greatly affected the human environment, New economies and institutions emerged, becoming more sophisticated and globally articulated over the course of the early modern period. This process began in the medieval North Italian city-states, particularly Genoa, Venice, the early modern period also included the rise of the dominance of the economic theory of mercantilism. The European colonization of the Americas, Asia, and Africa occurred during the 15th to 19th centuries, the early modern trends in various regions of the world represented a shift away from medieval modes of organization, politically and economically. Historians typically date the end of the modern period when the French Revolution of the 1790s began the modern period. Early modern themes Other In 16th century China, the Ming Dynastys economy was stimulated by trade with the Portuguese, Spanish. China became involved in a new trade of goods, plants, animals. Trade with Early Modern Europe and Japan brought in massive amounts of silver, during the last decades of the Ming the flow of silver into China was greatly diminished, thereby undermining state revenues and the entire Chinese economy. This damage to the economy was compounded by the effects on agriculture of the incipient Little Ice Age, natural calamities, crop failure, the ensuing breakdown of authority and peoples livelihoods allowed rebel leaders such as Li Zicheng to challenge Ming authority. The Ming Dynasty fell around 1644 to the Qing Dynasty, which was the last ruling dynasty of China, during its reign, the Qing Dynasty became highly integrated with Chinese culture. The Azuchi-Momoyama period saw the unification that preceded the establishment of the Tokugawa shogunate. The Edo period from 1600 to 1868 characterized early modern Japan, the Tokugawa shogunate was a feudal regime of Japan established by Tokugawa Ieyasu and ruled by the shoguns of the Tokugawa family. This period gets its name from the city, Edo. The Tokugawa shogunate ruled from Edo Castle from 1603 until 1868, in 1392, General Yi Seong-gye established the Joseon Dynasty with a largely bloodless coup. Joseon experienced advances in science and culture, King Sejong the Great promulgated hangul, the Korean alphabet. The period saw various other cultural and technological advances as well as the dominance of neo-Confucianism over the entirety of Korea, during the late 16th and early 17th centuries, invasions by the neighboring Japanese and Qing Chinese nearly overran the Korean peninsula

15.
Coffee
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Coffee is a brewed drink prepared from roasted coffee beans, which are the seeds of berries from the Coffea plant. The genus Coffea is native to tropical Africa, and Madagascar, the two most commonly grown are the highly regarded arabica, and the less sophisticated but stronger and more hardy robusta. Once ripe, coffee berries are picked, processed, and dried, dried coffee seeds are roasted to varying degrees, depending on the desired flavor. Roasted beans are ground and brewed with boiling water to produce coffee as a beverage. Coffee is slightly acidic and can have an effect on humans because of its caffeine content. Coffee is one of the most popular drinks in the world and it can be prepared and presented in a variety of ways. It is usually served hot, although iced coffee is also served, the earliest credible evidence of coffee-drinking appears in the middle of the 15th century in the Sufi shrines of Yemen. It was here in Arabia that coffee seeds were first roasted and brewed in a way to how it is now prepared. Coffee seeds were first exported from East Africa to Yemen, as the coffea arabica plant is thought to have been indigenous to the former, yemeni traders took coffee back to their homeland and began to cultivate the seed. By the 16th century, it had reached Persia, Turkey, from there, it spread to Europe and the rest of the world. Coffee is an export commodity, it is the top agricultural export for numerous countries and is among the worlds largest legal agricultural exports. It is one of the most valuable commodities exported by developing countries, green coffee is one of the most traded agricultural commodities in the world. Consequently, the markets for fair trade coffee and organic coffee are expanding. The first reference to coffee in the English language is in the form chaona, dated to 1598 and understood to be a misprint of chaoua, equivalent, in the orthography of the time, to chaova. This term and coffee both derive from the Ottoman Turkish kahve, by way of the Italian caffè and it has also been proposed that the source may be the Proto-Central Semitic root q-h-h meaning dark. Alternatively, the word Khat, a plant widely used as stimulant in Yemen and Ethiopia before being supplanted by coffee has been suggested as a possible origin, the expression coffee break was first attested in 1952. The term coffee pot dates from 1705, other accounts attribute the discovery of coffee to Sheikh Omar. According to the ancient chronicle, Omar, who was known for his ability to cure the sick through prayer, was exiled from Mocha in Yemen to a desert cave near Ousab

16.
Arabian Peninsula
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The Arabian Peninsula, simplified Arabia is a peninsula of Western Asia situated northeast of Africa on the Arabian plate. From a geological perspective, it is considered a subcontinent of Asia and it is the largest peninsula in the world, at 3,237,500 km2. The Arabian Peninsula consists of the countries Yemen, Oman, Qatar, Bahrain, Kuwait, Saudi Arabia, the Arabian Peninsula plays a critical geopolitical role in the Middle East and the Arab world due to its vast reserves of oil and natural gas. Before the modern era, it was divided into four regions, Hejaz, Najd, Southern Arabia. Hejaz and Najd make up most of Saudi Arabia, Southern Arabia consists of Yemen and some parts of Saudi Arabia and Oman. Eastern Arabia consists of the coastal strip of the Persian Gulf. The most prominent feature of the peninsula is desert, but in the southwest there are mountain ranges, harrat ash Shaam is a large volcanic field that extends from the northwestern Arabian Peninsula into Jordan and southern Syria. The peninsulas constituent countries are Kuwait, Bahrain, Qatar, the island nation of Bahrain lies off the east coast of the peninsula. Six countries form the Gulf Cooperation Council, however, this is a disputed term. The Kingdom of Saudi Arabia covers the part of the peninsula. The majority of the population of the live in Saudi Arabia. The peninsula contains the worlds largest reserves of oil, Saudi Arabia and the UAE are economically the wealthiest in the region. Qatar, a peninsula in the Persian Gulf on the larger peninsula, is home of the Arabic-language television station Al Jazeera. Kuwait, on the border with Iraq, is an important country strategically, though historically lightly populated, political Arabia is noted for a high population growth rate - as the result of both very strong inflows of migrant labor as well as sustained high birth rates. The population tends to be young and heavily skewed gender ratio dominated by males. In many states, the number of South Asians exceeds that of the local citizenry, the four smallest states, which have their entire coastlines on the Persian Gulf, exhibit the worlds most extreme population growth, roughly tripling every 20 years. In 2014, the population of the Arabian Peninsula was 77,983,936. Listed here are the human Y-chromosome DNA haplogroups in Arabia Haplogroup J is the most abundant component in the Arabian peninsula and its two main subclades, show opposite latitudinal gradients in the Middle East

17.
Arabic
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Arabic is a Central Semitic language that was first spoken in Iron Age northwestern Arabia and is now the lingua franca of the Arab world. Arabic is also the language of 1.7 billion Muslims. It is one of six languages of the United Nations. The modern written language is derived from the language of the Quran and it is widely taught in schools and universities, and is used to varying degrees in workplaces, government, and the media. The two formal varieties are grouped together as Literary Arabic, which is the language of 26 states. Modern Standard Arabic largely follows the standards of Quranic Arabic. Much of the new vocabulary is used to denote concepts that have arisen in the post-Quranic era, Arabic has influenced many languages around the globe throughout its history. During the Middle Ages, Literary Arabic was a vehicle of culture in Europe, especially in science, mathematics. As a result, many European languages have borrowed many words from it. Many words of Arabic origin are found in ancient languages like Latin. Balkan languages, including Greek, have acquired a significant number of Arabic words through contact with Ottoman Turkish. Arabic has also borrowed words from languages including Greek and Persian in medieval times. Arabic is a Central Semitic language, closely related to the Northwest Semitic languages, the Ancient South Arabian languages, the Semitic languages changed a great deal between Proto-Semitic and the establishment of the Central Semitic languages, particularly in grammar. Innovations of the Central Semitic languages—all maintained in Arabic—include, The conversion of the suffix-conjugated stative formation into a past tense, the conversion of the prefix-conjugated preterite-tense formation into a present tense. The elimination of other prefix-conjugated mood/aspect forms in favor of new moods formed by endings attached to the prefix-conjugation forms, the development of an internal passive. These features are evidence of descent from a hypothetical ancestor. In the southwest, various Central Semitic languages both belonging to and outside of the Ancient South Arabian family were spoken and it is also believed that the ancestors of the Modern South Arabian languages were also spoken in southern Arabia at this time. To the north, in the oases of northern Hijaz, Dadanitic and Taymanitic held some prestige as inscriptional languages, in Najd and parts of western Arabia, a language known to scholars as Thamudic C is attested

18.
Great Rift Valley, Ethiopia
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The Great Rift Valley of Ethiopia, is a branch of the East African Rift that runs through Ethiopia in a southwest direction from the Afar Triple Junction. In the past, it was seen as part of a Great Rift Valley that ran from Mozambique to Syria, the Great Rift Valley lies between the Ethiopian Plateau to the north and the Somalia Plateau to the south. The rift developed as the Nubian and Somalian plates began to separate during the Miocene Period along the East African rift system, the rift is extending in an ESE-WNW direction at about 5-7 millimetres annually. These faults are now thought to be inactive at the rift valley termination. The rift floor is cut by a series of en echelon, right-stepping. These basins are about 20 kilometres wide and 60 kilometres long, in the northern part of the rift, extension within the valley is now thought to be mainly along these faulted and magmatically active segments. These segments are considered to be developing mid ocean ridge spreading centers, the Ethiopian Rift Valley lakes are the northernmost of the African Rift Valley Lakes. The Ethiopian Rift Valley lakes occupy the floor of the valley between the two highlands. Most of the Ethiopian Rift Valley lakes do not have an outlet, the major ones are Lake Abaya, the largest Ethiopian Rift Valley lake Lake Chamo Lake Zway Lake Shala, the deepest Ethiopian Rift Valley lake Lake Koka Lake Langano Lake Abijatta Lake Awasa

19.
Tigray Region
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Tigray Region is the northernmost of the nine regions of Ethiopia. Tigray is the homeland of the Tigray, Irob and Kunama people, Tigray is also known as Region 1 according to the federal constitution. Tigray is bordered by Eritrea to the north, Sudan to the west, the Afar Region to the east, and the Amhara Region to the south and southwest. Besides Mekele, major cities include Hawzen, Abiy Addi, Alamata, Mekoni, Adigrat, Adwa, Axum, Humera, Korem, Maychew, Qwiha, Shire, Wukro, there is also the historically significant town of Yeha. For the history of the Tigray area prior to 1991, see Tigray Province, at the same time, a growing urban middle class of traders, businessmen and government officials emerged which was both suspicious and distant from the victorious EPRDF. In 1998, war erupted between Eritrea and Ethiopia over a portion of territory that had been administered at part of Tigray, with an estimated area of 41,409.95 square kilometers, this region has an estimated density of 100 people per square kilometer. In the previous census, conducted in 1994, the Regions population was 3,136,267, of whom 1,542,165 were men and 1,594,102 women, urban inhabitants numbered 621,210 or 14% of the population. According to the CSA, as of 2004,53. 99% of the population had access to safe drinking water. At 96. 55% of the population, the region is predominantly inhabited by the Tigrinya speaking Tigray people. The Tigrinya language is classified as belonging to the Semitic branch of the Afro-Asiatic family of languages, most other residents hail from other Afro-Asiatic speaking communities, including the Amhara, Irob, Afar, Agaw and Oromo. There are also a minority of Nilo-Saharan-speaking Kunama Nilotes, the working language is Tigrinya, although most urban people are also able to speak Amharic, which was taught in schools. A distinctive feature of Tigray are its rock-hewn churches, similar in design to those of Lalibela in the Amhara Region, these churches are found in four or five clusters – Gheralta, Teka-Tesfay, Atsbi and Tembien – with Wukro sometimes included. Some of the churches are considered earlier than those of Lalibela, mostly monolithic, with designs partly inspired by classical architecture, they are often located at the top of cliffs or steep hills, for security. For example, Tigrays ancient Debre Damo monastery is only by climbing a rope 25 meters up a sheer cliff. Looting has become an issue in the Tigray Region, as archaeological sites have become sources for construction materials. The area is famous for a single rock sculptured 23 meter long obelisk in Axum as well as for other fallen obelisks, the Axum treasure site of ancient Tigrayan history is a major landmark. Yeha is another important local landmark that is little-known outside the region

20.
Amhara Region
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Amhara is one of the nine ethnic divisions of Ethiopia, containing the homeland of the Amhara people. Previously known as Region 3, its capital is Bahir Dar, Ethiopias largest inland body of water, Lake Tana, which is the source of the Blue Nile river, is located within Amhara. The region also contains the Semien Mountains National Park, which includes Ras Dashan, during Ethiopias imperial era, Amhara included several provinces, most of which were ruled by native Ras or Negus. The Amhara Region then incorporated most of the provinces of Begemder, Dembiya, Angot, Bete Amhara, Gojjam. Especially, the re-designation of Wolkayit and Tsegede in Gondar as part of Tigray Region was rejected by its residents from the beginning, based on the 2007 census conducted by the Central Statistical Agency of Ethiopia, the Amhara Region has a population of 17,221,976. 8,641,580 were men and 8,580,396 women, with an estimated area of 159,173.66 square kilometers, this region has an estimated density of 108.2 people per square kilometer. According to the CSA, as of 2004, 28% of the population had access to safe drinking water. At 91. 47% of the population, the region is predominantly inhabited by people from the Semitic-speaking Amhara ethnic group. Most other residents hail from other Afro-Asiatic language communities, including the Agaw/Awi, Oromo, Agaw/Kamyr, the Amhara Highlands receive 80% of the total rainfall of Ethiopia and is the most fertile and hospitable regions of Ethiopia. The The Amhara Region is the location of Laka Tana, the source of the Blue Nile, the flow of the Blue Nile reaches maximum volume in the rainy season, when it supplies about two-thirds of the water of the Nile proper. The Blue Nile, along with the Atbara River to the north and this supported the rise of ancient Egyptian civilization and Egyptian Mythology. With the completion in 1970 of the Aswan High Dam in Egypt, Lake Tana has a number of islands, whose numbers vary depending on the level of the lake, it has fallen about 2 metres in the last 400 years. According to Manoel de Almeida, there were 21 islands, seven to eight of which had monasteries on them formerly large, but now much diminished. When James Bruce visited the area in the later 18th century, he noted that the locals counted 45 inhabited islands, a mid-twentieth century account identified 37 islands, of which 19 were said to have or have had monasteries or churches on them. The lake islands were the home of ancient Ethiopian emperors, treasures of the Ethiopian Church are kept in the isolated island monasteries. The body of Yekuno Amlak is interred in the monastery of St. Stephen on Daga Island, other Emperors whose tombs are on Daga include Dawit I, Zara Yaqob, Za Dengel and Fasilides. Other important islands in Lake Tana include Dek, Mitraha, Gelila Zakarias, Halimun, in the late 20th century, the scholar Paul B. Henze reported being shown a rock on the island of Tana Qirqos and he was also told that Saint Frumentius, the bishop known for introducing Christianity to Ethiopia, was allegedly buried on Tana Cherqos

21.
Lake Tana
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Lake Tana is the source of the Blue Nile and is the largest lake in Ethiopia. Lake Tana is fed by the Lesser Abay, Reb and Gumara rivers and its surface area ranges from 3,000 to 3,500 km, ² depending on season and rainfall. The lake level has been regulated since the construction of the control weir where the lake discharges into the Blue Nile and this controls the flow to the Blue Nile Falls and hydro-power station. Lake Tana was formed by volcanic activity, blocking the course of inflowing rivers in the early Pleistocene epoch, the lake was originally much larger than it is today. Seven large permanent rivers feed the lake as well as 40 small seasonal rivers, the main tributaries to the lake are Gilgel Abbay, and the Megech, Gumara, and Rib rivers. Lake Tana has a number of islands, whose number varies depending on the level of the lake and it has fallen about 6 feet in the last 400 years. According to Manoel de Almeida, there were 21 islands, seven to eight of which had monasteries on them formerly large, but now much diminished. When James Bruce visited the area in the later 18th century, he noted that the locals counted 45 inhabited islands, a 20th-century geographer named 37 islands, of which he believed 19 have or had monasteries or churches on them. Remains of ancient Ethiopian emperors and treasures of the Ethiopian Church are kept in the isolated island monasteries, on the island of Tana Qirqos is a rock shown to Paul B. Henze, on which he was told the Virgin Mary had rested on her back from Egypt, he was also told that Frumentius. The body of Yekuno Amlak is interred in the monastery of St. Stephen on Daga Island, emperors whose tombs are also on Daga include Dawit I, Zara Yaqob, Za Dengel, and Fasilides. Other important islands in Lake Tana include Dek, Mitraha, Gelila Zakarias, Halimun, the monasteries are believed to have been built over earlier religious sites. They include the fourteenth-century Debre Maryam, and the eighteenth-century Narga Selassie, Tana Qirqos, a ferry service links Bahir Dar with Gorgora via Dek Island and various lakeshore villages. There is also Zege Peninsula on the southwest portion of the lake, Zege is the site of the Azwa Maryam monastery. About 70% of the species in the lake are endemic. This includes one of two known cyprinid species flocks, which consists of fifteen relatively large, up to 1 m long. Eight of these are piscivorous and an important prey is the small Barbus tanapelagius, other noteworthy endemic species are Afronemacheilus abyssinicus, which is one of only two African stone loaches, and the tana subspecies of the Nile tilapia. Lake Tana supports a fishing industry, mainly based on the Labeobarbus barbs, Nile tilapia

22.
Blue Nile
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The Blue Nile is a river originating at Lake Tana in Ethiopia. With the White Nile, the river one of the two major tributaries of the Nile. The upper course of the river is called the Abbay in Ethiopia, some Ethiopians have long identified the Blue Nile as the River Gihon mentioned as flowing out of the Garden of Eden, in Genesis 2 and encircling the entire land of Cush. In the local Sudanese language, the word for black is used for the colour blue. The distance of the river from its source to its confluence has been reported as being between 1,460 kilometres and 1,600 kilometres. According to materials published by the Central Statistical Agency, the Blue Nile has a length of 1,450 kilometres. The Blue Nile flows generally south from Lake Tana and then west across Ethiopia, within 30 km of its source at Lake Tana, the river enters a canyon about 400 km long. This gorge is an obstacle for travel and communication from the north half of Ethiopia to the southern half. The power of the Blue Nile may best be appreciated at the Blue Nile Falls and this stream, known as the Lesser Abay River, flows north into Lake Tana. Other affluents of this include, in clockwise order from Gorgora, the Magech River, the Northern Gumara, the Reb River, the southern Gumara River. Lake Tanas outflow then flows some 30 kilometres before plunging over the Blue Nile Falls, the river then loops across northwest Ethiopia through a series of deep valleys and canyons into Sudan, by which point it is only known as the Blue Nile. There are numerous tributaries of the Abay between Lake Tana and the Sudanese border. Those on the side, also in downstream order, include the Handassa, Tul, Abaya, Sade, Tammi, Cha, Shita, Suha, Muga, Gulla, Temcha, Bachat, Katlan, Jiba, Chamoga, Weter. The flow of the Blue Nile reaches maximum volume in the rainy season, the Blue Nile was a major source of the flooding of the Nile that contributed to the fertility of the Nile Valley and the consequent rise of Ancient Egypt and Egyptian mythology. With the completion in 1970 of the Aswan Dam in Egypt, the Blue Nile is vital to the livelihood of Egypt. The Blue Nile, the most significant tributary of the Nile, though shorter than the White Nile, 59% of the water that reaches Egypt originates from the Blue Nile branch of the great river. The river is also an important resource for Sudan, where the Roseires Dam and these dams also help irrigate the Gezira Scheme, which is most famous for its high quality cotton. The region also produces wheat and animal feed crops, in November 2012, Ethiopia began a six-year project for the construction of the Grand Ethiopian Renaissance Dam, a 6000-megawatt hydroelectric dam on the river

23.
Bale Zone
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Bale is one of the zones in the Oromia Region of Ethiopia. Bale is named for the former Sultanate of Bale, which was in approximately the same area, the highest point in the Bale Zone, and also the highest point in Oromia, is Mount Batu in the Urgoma Mountains range. Other notable peaks of the Urgoma include Mount Tullu Dimtu, Mount Darkeena, rivers include the Wabe and the Weyib, notable lakes include Garba Guracha and Hora Orgona. Points of interest in the Zone include Sheikh Hussein—named for the tomb of a Moslem saint—the Bale Mountains National Park, towns and cities in Bale include Dodola, Ginir, Goba and Robe. This represents 4. 46% of the Regions output and 2. 2% of Ethiopias total output, while 166,758 or 26. 20% are urban inhabitants, a further 44,610 or 3. 18% are pastoralists. A total of 297,081 households were counted in this Zone, which results in an average of 4.72 persons to a household, and 287,188 housing units. The three largest ethnic groups reported were the Oromo, the Amhara and the Somali, all ethnic groups made up 1. 66% of the population. Oromiffa was spoken as a first language by 90. 46%, Amharic was spoken by 7. 11% and Somali by 1. 05%, the remaining 1. 38% spoke all other primary languages reported. The four largest ethnic groups reported in Bale were the Oromo, the Amhara, the Somali, and the Sidama, all other ethnic groups made up 1. 15% of the population. Oromiffa was spoken as a first language by 87. 5%,9. 5% Amharic,1. 51% spoke Somali, and 0. 88% spoke Sidamo, the remaining 0. 61% spoke all other primary languages reported. 19. 5% of the population is in non-farm related jobs, compared to the average of 25%. Concerning education, 66% of all children are enrolled in primary school. Concerning health, 53% of the zone is exposed to malaria, the memorandum gave this zone a drought risk rating of 555

24.
Oromia Region
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Oromia is one of the nine ethnically based regional states of Ethiopia, covering 284,538 square kilometers. The 2007 census reported Oromia Region population is 26,993,933, making it the largest state in population, Oromia includes the former Arsi Province along with portions of the former Bale, Hararghe, Illubabor, Kaffa, Shewa, Sidamo, and Welega provinces. The Region was the scene of protests and a government crackdown which killed dozens of protesters in August 2016. The region of Oromia Region was inhabited by ethnic communities for centuries. The earliest people to live in Oromia Region were the muslim Gurage people from southern Ethiopia, most of these ancient Kingdoms situated in present-day Oromia Region were semi-autonomous provinces of Ethiopian Empire. After the brutal conquest of these region by the Oromo people, the affiliated groups were given new genealogies and started counting their putative ancestors in the same way as their adoptive kinsmen. The native ancient names of the territories were replaced by the name of the Oromo clans who conquered it, before 2000, the regional capital of Oromia was Addis Ababa, also known as Finfinne. The relocation of the capital to Adama sparked considerable controversy. Critics of the believed the Ethiopian government wished to de-emphasize Addis Ababas location within Oromia. On the other hand, the government maintained that Addis Ababa has been found inconvenient from the point of view of developing the language, culture and history of the Oromo people. On 10 June 2005, the Oromo Peoples Democratic Organization, part of the ruling coalition, Oromia shares a boundary with almost every region of Ethiopia except for the Tigray Region. This boundary has been disputed with Oromias neighbors in a number of cases, one attempt to resolve the dispute between the two regions was the October 2004 referendum held in about 420 kebeles in 12 woredas across five zones of the Somali Region. According to the results of the referendum, about 80% of the disputed areas have fallen under Oromia administration. The results led over the weeks to minorities in these kebeles being pressured to leave. Federal authorities believe that number may be overstated by as much as 11,000. In Doba, the Ministry of Federal Affairs put the number of IDPs at 6,000, there are also more than 2,500 displaced persons in Mieso. In addition, there were reports of people being displaced in the area of Moyale. On 5 August 2016 protests broke out across Ethiopia and centered around the Oromia Region, dozens of protesters were killed in the first days of the protests and internet service was cut to many parts of the region. 3% of the population

25.
Bale Mountains
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The Bale Mountains, in the Oromia Region of southeast Ethiopia, south of the Awash River, are part of the Ethiopian Highlands. They include Tullu Demtu, the second-highest mountain in Ethiopia, the Weyib River, a tributary of the Jubba River, rises in these mountains east of Goba. The Bale Mountains National Park covers 2,200 square kilometers of these mountains, the main attractions of the park are the wild alpine scenery, and the relative ease with which visitors can see unique birds and mammals. The Bale Mountains are home to many of Ethiopias endemic animals, notably the Ethiopian wolf, besides wildlife, the National Park offers trekking opportunities from the park headquarters at Dinsho. The largest group of Ethiopian wolves is found here, other characteristic large mammals are mountain nyalas, Meneliks bushbucks, warthogs, and bohor reedbucks. The Juniper-Hagenia forests lie between 2,500 and 3,300 m and are found on the northern slopes. An unusual plant of the Dinsho area is the white-flowered Abyssinian rose, the alpine moorland of the Saneti Plateau is covered in heath-like vegetation broken by heather plants and stands of giant lobelia which grow up to 6 meters high. One of the most common and distinctive plants throughout the Bale region is the red-hot poker, an aloe which can be identified by its orange spear-shaped flowers

26.
Bale Mountains National Park
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Bale Mountains National Park is a national park of Ethiopia. The park encompasses an area of approximately 2,150 square kilometres in the Bale Mountains, the parks Afromontane habitats have one of the highest incidences of animal endemicity of any terrestrial habitat in the world. The park was nominated to the World Heritage Tentative List in 2009, Bale Mountains National Park is located in southeastern Ethiopia,400 km southeast of Addis Ababa and 150 km east of Shashamene in the Oromia Region National State. The boundary of the BMNP lies within five woredas, Adaba, Dinsho, Goba, Delo-Mena-Angetu, the park area is encompassed within geographical coordinates of 6º29 – 7º10N and 39º28 – 39º57E. The Bale Mountains are part of the Bale-Arsi massif, which forms the western section of the southeastern Ethiopian Highlands. The Bale Mountains were formed prior to the formation of the Great Rift Valley, the rocks of the volcanic outpourings are predominantly trachytes, but also include rhyolites, basalts, and associated agglomerates and tuffs. The main Bale highlands consist of the vast lava Sanetti Plateau, with at least six volcanic cones, each more than 4,200 meters high and considerably flattened by repeated glaciations. There have been at least two periods in the history of the mountains and they were glaciated as little as 2,000 years ago. During the Last ice age, the Bale Mountains were one of the most extensively glaciated areas in present day Ethiopia, with a total area of ice in Bale of approximately 180 km2. There was a 30 km2 ice cap around the peak of Tulu Dimtu on the Sanetti Plateau, as a consequence, the landscape as we see it today is the lava outpourings much modified by over 20 million years of erosion by water, wind and ice. There are certain features that remain an enigma to geologists and glaciologists such as the striations that appear on shallow hillsides on the Sanetti Plateau. Until the beginning of deglaciation the snowline was at 3,700 meters, fluctuations in climate over the last historical period, including the last 3,000 years, have dramatically affected the vegetation and other biodiversity in the highlands. The Bale Mountains play a role in climate control of the region by attracting large amounts of orographic rainfall. A total of 40 rivers rise in the BMNP area, contributing to five major rivers, additionally, the Bale massif is the source for many springs in the lowlands, which are of paramount importance as they are the only source of water year-round. People living south of the park are completely dependent on good management of the water resources from the highland areas. If such a situation arises, the dry season range of the people and their livestock reduces dramatically and it is widely recognized that such uneven distribution of people and livestock leads to rapid and lasting degradation. The people are, therefore, likely to become increasingly food-aid dependent if the catchment areas of the Bale Mountains are insufficiently protected. There is already evidence that over abstraction of water in the Bale Mountains is occurring, furthermore, two rivers emanating from Bale, the Wabe Shebele and Yadot, have hydroelectric schemes

27.
Gondar
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Gondar or Gonder is a city and separate woreda in Ethiopia. Located in the Semien Gondar Zone of the Amhara Region, Gondar is north of Tana Lake on the Lesser Angereb River and it has a latitude and longitude of 12°36′N 37°28′E with an elevation of 2133 meters above sea level. It is surrounded by the Gondar Zuria woreda, Gondar previously served as the capital of both the Ethiopian Empire and the subsequent Begemder Province. The city holds the remains of royal castles, including those in Fasil Ghebbi. One exception to rule was Debre Berhan, founded by Zara Yaqob in 1456. Beginning with Emperor Menas in 1559, the rulers of Ethiopia began spending the season near Lake Tana. These encampments, which flourished as cities for a time, include Emfraz, Ayba, Gorgora. Gondar was founded by Emperor Fasilides around the year 1635, and grew as an agricultural, there was a superstition at the time that the capitals name should begin with the letter Gʷa, which also contributed to Gorgoras growth in the centuries after 1600. Tradition also states that a buffalo led the Emperor Fasilides to a pool beside the Angereb, Fasilides had the pool filled in and built his castle on that same site. The emperor also built a total of seven churches, the first two, Fit Mikael and Fit Abbo, were built to end local epidemics, the five emperors who followed him also built their palaces in the town. In 1668, as a result of a council, the Emperor Yohannes I ruled that the inhabitants of Gondar are to be segregated by religion. This caused the Muslims to move into their own quarter, Islamge or Islam Bayt and this quarter came to be known as Addis Alem. During the seventeenth century, the population is estimated to have exceeded 60,000. Many of the buildings from this period survive, despite the turmoil of the eighteenth century, although Gondar was by any definition a city, it was not a melting pot of diverse traditions, nor Ethiopias window to the larger world, according to Donald Levine. It served rather as an agent for the development of the Amharas own culture. And thus it became a focus of national pride, not as a hotbed of alien custom and immorality, as they often regard Addis Ababa today, but as the most perfect embodiment of their traditional values. As Levine elaborates in a footnote, it was a pattern of development. Abdallahi ibn Muhammad sacked Gondar when he invaded Ethiopia June 1887, Gondar was ravaged again on 23 January in the next year, when Sudanese invaders set fire to almost every one of the citys churches

28.
Axum
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Axum or Aksum is a city in the northern part of Ethiopia. The town has a population of 56,500 residents, and is governed as an urban wäräda, the original capital of the Kingdom of Aksum, it is one of the oldest continuously inhabited places in Africa. Axum was a naval and trading power that ruled the region from about 400 BCE into the 10th century, in 1980 UNESCO added Aksums archaeological sites to its list of World Heritage Sites due to their historic value. Located in the Mehakelegnaw Zone of the Tigray Region near the base of the Adwa mountains, Axum is surrounded by Lailay Maychew wäräda. Axum was the center of the trading power known as the Aksumite Kingdom. Around 356 CE, its ruler was converted to Christianity by Frumentius, later, under the reign of Kaleb, Axum was a quasi-ally of Byzantium against the Sasanian Persian Empire which had adopted Zoroastrianism. The historical record is unclear, with ancient church records the primary contemporary sources and it is believed it began a long slow decline after the 7th century due partly to the Persians and finally the Arabs contesting old Red sea trade routes. Eventually Aksum was cut off from its principal markets in Alexandria, Byzantium and Southern Europe, the Kingdom of Aksum was finally destroyed by Gudit, and eventually some of the people of Aksum were forced south and their civilization declined. As the kingdoms power declined so did the influence of the city, the last known king to reign was crowned in about the 10th century, but the kingdoms influence and power ended long before that. Its decline in population and trade contributed to the shift of the power center of the Ethiopian Empire south to the Agaw region as it moved further inland. The city of Axum was the seat of an empire spanning 1 million square miles. Eventually, the name was adopted by the central region, and subsequently. The Kingdom of Axum had its own language, Geez, and developed a distinctive architecture exemplified by giant obelisks. The kingdom was at its height under King Ezana, baptized as Abreha, the historical records and Ethiopian traditions suggest that it was from Axum that Makeda, the Queen of Sheba, journeyed to visit King Solomon in Jerusalem. She had a son, Menelik, fathered by Solomon and he grew up in Ethiopia but traveled to Jerusalem as a young man to visit his fathers homeland. He lived several years in Jerusalem before returning to his country with the Ark of the Covenant, according to the Ethiopian Church and Ethiopian tradition, the Ark still exists in Axum. This same church was the site where Ethiopian emperors were crowned for centuries until the reign of Fasilides, Axum is considered to be the holiest city in Ethiopia and is an important destination of pilgrimages. Significant religious festivals are the Timkat festival on 19 January and the Festival of Maryam Zion on November 24

29.
Arabian-Nubian Shield
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The Arabian-Nubian Shield is an exposure of Precambrian crystalline rocks on the flanks of the Red Sea. The crystalline rocks are mostly Neoproterozoic in age, geographically - and from north to south - the ANS includes the nations of Israel, Jordan. Egypt, Saudi Arabia, Sudan, Eritrea, Ethiopia, Yemen, the ANS in the north is exposed as part of the Sahara Desert and Arabian Desert, and in the south in the Ethiopian Highlands, Asir province of Arabia and Yemen Highlands. The ANS was the site of some of mans earliest geologic efforts, principally by the Egyptians to extract gold from the rocks of Egypt and this was the most easily worked of all metals and does not tarnish. All of the deposits in Egypt and northern Sudan were found and exploited by Egyptians, but new gold discoveries have been found in Sudan, Eritrea. Pharonic Egyptians also quarried granite near Aswan and floated this down the Nile to be used as facing for the pyramids, the earliest preserved geologic map was made in 1150 BCE to show the location of gold deposits in Eastern Egypt, it is known as the Turin papyrus. The Greek name for Aswan, Syene, is the locality for the igneous rock syenite. The Romans followed this tradition and had many quarries especially in the part of the Eastern Desert of Egypt where porphyry. Precious and industrial metals, including gold, silver, copper, zinc, tin, today, mining at Mahd adh Dhahab is conducted by the Saudi Arabian Mining Company, Maaden. Deposits of iron, tungsten, mineral sands, copper and phosphates have been found in many locations, Mining in the Eastern Desert of Egypt and Sudan is limited due to shortage of water and infrastructure. One option would be to bring water from the Nile by pipeline, the exposed Arabian Shield in Saudi Arabia encompasses ≈445,000 km2. The total Arabian Shield, including exposed parts plus what is hidden by younger lava flows and sediments, Exposed Shield rocks in Jordan and Yemen cover another ≈100,000 km sq. This equals ≈825,000 km2 for the Arabian side of the ANS. For the Nubian Shield, which is exposed in Egypt, Sudan, Eritrea, Ethiopia, S. Sudan and this gives a total estimated area for the Nubian Shield ≈1,901,000 km2. The total area of exposed and inferred ANS ≈2,725,000 km2 and this is slightly less than 30% of the area of the USA and 2% of Earths continental area. The Arabian-Nubian Shield is representative of the continental crust that underlies NE Africa, SW Asia, geophysical studies inform us that ANS crust is about 40–45 km thick, typical for continental crust elsewhere. Geologists are interested to study this crust because it provides an opportunity to learn how continental crust forms. Elsewhere in Arabia and NE Africa the crust is buried beneath kilometers of younger, Phanerozoic sediments and this is exposed in spectacular cliffs like the site of Petra in Jordan

30.
Red Sea
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The Red Sea is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait, to the north lie the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez. The Red Sea is a Global 200 ecoregion, the sea is underlain by the Red Sea Rift which is part of the Great Rift Valley. The Red Sea has an area of roughly 438,000 km2, is about 2250 km long and. It has a depth of 2211 m in the central median trench. However, there are also extensive shallow shelves, noted for their marine life, the sea is the habitat of over 1,000 invertebrate species, and 200 soft and hard corals. It is the worlds northernmost tropical sea, the International Hydrographic Organization defines the limits of the Red Sea as follows, On the North. The Southern limits of the Gulfs of Suez and Aqaba, a line joining Husn Murad and Ras Siyyan. Red Sea is a translation of the Greek Erythra Thalassa, Latin Mare Rubrum, Arabic, البحر الأحمر‎. Al-Baḥr Al-Aḥmar‎, Somali Badda Cas and Tigrinya Qeyyiḥ bāḥrī, the name of the sea may signify the seasonal blooms of the red-coloured Trichodesmium erythraeum near the waters surface. A theory favored by modern scholars is that the name red is referring to the direction south. The basis of this theory is that some Asiatic languages used color words to refer to the cardinal directions, herodotus on one occasion uses Red Sea and Southern Sea interchangeably. Historically, it was known to western geographers as Mare Mecca. Some ancient geographers called the Red Sea the Arabian Gulf or Gulf of Arabia. C, in that version, the Yam Suph is translated as Erythra Thalassa. The Red Sea is one of four seas named in English after common color terms — the others being the Black Sea, the White Sea and the Yellow Sea. The direct rendition of the Greek Erythra thalassa in Latin as Mare Erythraeum refers to the part of the Indian Ocean. The earliest known exploration of the Red Sea was conducted by ancient Egyptians, one such expedition took place around 2500 BC, and another around 1500 BC. Both involved long voyages down the Red Sea, historically, scholars argued whether these trips were possible

31.
Gulf of Aden
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The Gulf of Aden is a gulf located in the Arabian Sea between Yemen, on the south coast of the Arabian Peninsula, and Somalia in the Horn of Africa. In the northwest, it connects with the Red Sea through the Bab-el-Mandeb strait and it shares its name with the port city of Aden in Yemen, which forms the northern shore of the gulf. Historically, the Gulf of Aden was known as The Gulf of Berbera, however, as the city of Aden grew during the colonial era, the name of Gulf of Aden was popularised. The waterway is part of the important Suez Canal shipping route between the Mediterranean Sea and the Arabian Sea in the Indian Ocean with 21,000 ships crossing the gulf annually. The name of the Gulf was inspired by the former British Crown Colony city of Aden, the Somali names are Gacanka Cadmeed or Gacanka Saylac. The International Hydrographic Organization defines the limits of the Gulf of Aden as follows, on the Northwest – The eastern limit of the Gulf of Tadjoura. On the East – The meridian of Cape Guardafui, the temperature of the Gulf of Aden varies between 15 °C and 28 °C, depending on the season and the appearance of monsoons. The Gulf of Aden is a waterway for shipping, especially for Persian Gulf oil. Approximately 11 percent of the worlds petroleum passes through the Gulf of Aden on its way to the Suez Canal or to regional refineries. The main ports along the gulf are Aden in Yemen, Djibouti City in Djibouti, in earlier history, the city of Crater, located just south of the modern city of Aden, was an important port in regional trade. In the late 2000s, the gulf evolved into a hub of pirate activity, by 2013, attacks in the waters had steadily declined due to active private security and international navy patrols. India receives USD50 billion in imports and sends USD60 billion in exports through this area annually, because of this and for the sake of protecting the trade of other countries, India keeps a warship escort in this area. Also see Piracy in Gulf of Aden, a geologically young body of water, the Gulf of Aden has a unique biodiversity that contains many varieties of fish, coral, seabirds and invertebrates. This rich ecological diversity has benefited from a lack of pollution during the history of human habitation around the gulf. However, environmental groups fear that the lack of an effort to control pollution may jeopardize the gulfs ecosphere. Whales, dolphins, and dugongs were common before being severely reduced by commercial hunts, including by mass illegal hunts by Soviet Union

32.
Ethiopia-Yemen Continental Flood Basalts
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The Ethiopia-Yemen Continental Flood Basalts were erupted during the Oligocene. They cover an area of about 600,000 km2 in Yemen and Ethiopia and they are associated with the Afar Plume and the initiation of rifting in the southern Red Sea and Gulf of Aden. The lavas of the Ethiopia-Yemen CFB show systematic variations in composition both vertically and laterally, the sequence is also an example of bimodal volcanism and the uppermost part typically contains significant amounts of rhyolitic lavas

33.
Basalt
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Basalt is a common extrusive igneous rock formed from the rapid cooling of basaltic lava exposed at or very near the surface of a planet or moon. Flood basalt describes the formation in a series of basalt flows. By definition, basalt is an igneous rock with generally 45-55% silica and less than 10% feldspathoid by volume. Basalt commonly features a very fine-grained or glassy matrix interspersed with visible mineral grains, the average density is 3.0 gm/cm3. Basalt is defined by its content and texture, and physical descriptions without mineralogical context may be unreliable in some circumstances. Basalt is usually grey to black in colour, but rapidly weathers to brown or rust-red due to oxidation of its mafic minerals into hematite, although usually characterized as dark, basaltic rocks exhibit a wide range of shading due to regional geochemical processes. Due to weathering or high concentrations of plagioclase, some basalts can be quite light-coloured and these phenocrysts usually are of olivine or a calcium-rich plagioclase, which have the highest melting temperatures of the typical minerals that can crystallize from the melt. Basalt with a texture is called vesicular basalt, when the bulk of the rock is mostly solid. Gabbro is often marketed commercially as black granite and these ultramafic volcanic rocks, with silica contents below 45% are usually classified as komatiites. Agricola applied basalt to the black rock of the Schloßberg at Stolpen. Tholeiitic basalt is relatively rich in silica and poor in sodium, included in this category are most basalts of the ocean floor, most large oceanic islands, and continental flood basalts such as the Columbia River Plateau. Basalt rocks are in some cases classified after their content in High-Ti and Low-Ti varieties. High-Ti and Low-Ti basalts have been distinguished in the Paraná and Etendeka traps and it has greater than 17% alumina and is intermediate in composition between tholeiite and alkali basalt, the relatively alumina-rich composition is based on rocks without phenocrysts of plagioclase. Alkali basalt is relatively poor in silica and rich in sodium and it is silica-undersaturated and may contain feldspathoids, alkali feldspar and phlogopite. Boninite is a form of basalt that is erupted generally in back-arc basins. Ocean island basalt Lunar basalt On Earth, most basalt magmas have formed by melting of the mantle. Basalt commonly erupts on Io, the third largest moon of Jupiter, and has formed on the Moon, Mars, Venus. The crustal portions of oceanic tectonic plates are composed predominantly of basalt, produced from upwelling mantle below, the mineralogy of basalt is characterized by a preponderance of calcic plagioclase feldspar and pyroxene

34.
Tholeiitic magma series
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The tholeiitic magma series, named after the German municipality of Tholey, is one of two main magma series in igneous rocks, the other magma series being the calc-alkaline. A magma series is a series of compositions that describes the evolution of a mafic magma, the International Union of Geological Sciences recommends that tholeiitic basalt be used in preference to the term tholeiite. Rocks in the tholeiitic magma series are classified as subalkaline and are distinguished from rocks in the calc-alkaline magma series by the state of the magma they crystallized from. The difference between these two series can be seen on an AFM diagram, a ternary diagram showing the relative proportions of the oxides Na2O + K2O, FeO + Fe2O3. As magmas cool, they precipitate out significantly more iron and magnesium than alkali, like all basalt, the rock type is dominated by clinopyroxene plus plagioclase, with minor iron-titanium oxides. Orthopyroxene or pigeonite may also be present in tholeiitic basalt, and olivine, if present, tridymite or quartz may be present in the fine-grained groundmass of tholeiitic basalt, and feldspathoids are absent. Tholeiitic rocks may have a fine, glassy groundmass, as may other types of basalt, basalt magmas are partial melts of peridotite produced by decompression melting in the Earths mantle, a process described for igneous rocks. Tholeiitic basalts are the most common volcanic rocks on Earth, as they are produced by submarine volcanism at mid-ocean ridges, MORB, the acronym for typical mid-ocean-ridge basalt, is a type of tholeiitic basalt particularly low in incompatible elements. In contrast, alkali basalt is not typical at ocean ridges, because the Moon is extremely reduced, all of its basalt is tholeiitic. Petrology Igneous differentiation R. W. Le Maitre, A. Streckeisen, zanettin, M. J. Le Bas, B

35.
Felsic
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In geology, felsic refers to igneous rocks that are relatively rich in elements that form feldspar and quartz. It is contrasted with mafic rocks, which are richer in magnesium. It refers to those rocks rich in minerals, magma, and rocks which are enriched in the lighter elements such as silicon, oxygen, aluminium, sodium. They are usually light in color and have specific gravities less than 3, the most common felsic rock is granite. Common felsic minerals include quartz, muscovite, orthoclase, and the sodium-rich plagioclase feldspars, in terms of chemistry, felsic minerals and rocks are at the other end of the elemental spectrum from the mafic minerals and rocks. In modern usage, the acid rock, although sometimes used as a synonym, refers to a high-silica-content volcanic rock. The term was used broadly in older geologic literature. It is considered archaic now, as the acidic and basic rock were based on an incorrect idea, dating from the 19th century. The term felsic combines the words feldspar and silica, in order for a rock to be classified as felsic, it generally needs to contain more than 75% felsic minerals, namely quartz, orthoclase and plagioclase. Rocks with greater than 90% felsic minerals can also be called leucocratic, the chemical name of a felsic rock is given according to the TAS classification of Le Maitre. However, this applies to volcanic rocks. If the rock is analyzed and found to be felsic but is metamorphic and has no definite volcanic protolith, there are examples known of highly sheared granites which can be mistaken for rhyolites. For phaneritic felsic rocks, the QAPF diagram should be used, the rock texture thus determines the basic name of a felsic rock. QAPF diagram List of minerals List of rock types Le Maitre, igneous Rocks, A Classification and Glossary of Terms 2nd edition, Cambridge

36.
Rhyolite
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Rhyolite is an igneous, volcanic rock, of felsic composition. It may have any texture from glassy to aphanitic to porphyritic, the mineral assemblage is usually quartz, sanidine and plagioclase. Biotite and hornblende are common accessory minerals and it is the extrusive equivalent to granite. Rhyolite can be considered as the equivalent to the plutonic granite rock. Due to their content of silica and low iron and magnesium contents, rhyolite melts are highly polymerized. They also occur as breccias or in volcanic plugs and dikes, rhyolites that cool too quickly to grow crystals form a natural glass or vitrophyre, also called obsidian. Slower cooling forms microscopic crystals in the lava and results in such as flow foliations, spherulitic, nodular. Some rhyolite is highly vesicular pumice, many eruptions of rhyolite are highly explosive and the deposits may consist of fallout tephra/tuff or of ignimbrites. Eruptions of rhyolite are relatively rare compared to eruptions of less felsic lavas, etsch Valley Vulcanite Group near Bolzano and the surrounding area Gréixer rhyolitic complex at Moixeró range Vosges Iceland, all active and extinct central volcanoes, e. g. g. Wichita Mountains within the Southern Oklahoma Aulacogen St, in North American pre-historic times, rhyolite was quarried extensively in eastern Pennsylvania in the United States. Among the leading quarries was the Carbaugh Run Rhyolite Quarry Site in Adams County, comendite List of rock types Pantellerite Thunderegg University of North Dakota description of rhyolite Information from rocks-rock. com

37.
Caldera
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A caldera is a large cauldron-like depression that forms following the evacuation of a magma chamber/reservoir. When large volumes of magma are erupted over a time period. The ground surface then collapses downward into the emptied magma chamber. Although sometimes described as a crater, the feature is actually a type of sinkhole, as it is formed through subsidence, only seven known caldera-forming collapses have occurred since the start of the 20th century, most recently at Bárðarbunga volcano in Iceland. The word comes from Spanish caldera, and this from Latin caldaria, in some texts the English term cauldron is also used. If enough magma is ejected, the chamber is unable to support the weight of the volcanic edifice above it. A roughly circular fracture, the fault, develops around the edge of the chamber. Ring fractures serve as feeders for fault intrusions which are known as ring dykes. Secondary volcanic vents may form above the ring fracture, as the magma chamber empties, the center of the volcano within the ring fracture begins to collapse. The collapse may occur as the result of a cataclysmic eruption. The total area that collapses may be hundreds or thousands of square kilometers, some calderas are known to host rich ore deposits. One of the worlds best-preserved mineralized calderas is the Sturgeon Lake Caldera in northwestern Ontario, Canada, if the magma is rich in silica, the caldera is often filled in with ignimbrite, tuff, rhyolite, and other igneous rocks. Silica-rich magma has a high viscosity, and therefore does not flow easily like basalt, as a result, gases tend to become trapped at high pressure within the magma. Further lava flows may be erupted, if volcanic activity continues, the center of the caldera may be uplifted in the form of a resurgent dome such as is seen at Cerro Galán, Lake Toba, Yellowstone, etc. by subsequent intrusion of magma. A silicic or rhyolitic caldera may erupt hundreds or even thousands of kilometers of material in a single event. Even small caldera-forming eruptions, such as Krakatoa in 1883 or Mount Pinatubo in 1991, may result in significant local destruction, large calderas may have even greater effects. When Yellowstone Caldera last erupted some 650,000 years ago, it released about 1,000 km3 of material, by comparison, when Mount St. Helens erupted in 1980, it released ~1.2 km3 of ejecta. The ecological effects of the eruption of a large caldera can be seen in the record of the Lake Toba eruption in Indonesia, more recently several geneticists, including Lynn Jorde and Henry Harpending have proposed that the human species was reduced to approximately five to ten thousand people

38.
Alkaline
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Alkalinity is the name given to the quantitative capacity of an aqueous solution to neutralize an acid. Measuring alkalinity is important in determining a streams ability to neutralize acidic pollution from rainfall or wastewater and it is one of the best measures of the sensitivity of the stream to acid inputs. There can be changes in the alkalinity of streams and rivers in response to human disturbances. Alkalinity is related to the pH of a solution, but measures a different property, roughly, the alkalinity of a solution is a measure of how strong the bases are in a solution, whereas the pH measures the amount of chemical bases. A good example is a solution, which can have many available bases despite having only a moderate pH level. Alkalinity roughly refers to the amount of bases in a solution that can be converted to uncharged species by a strong acid. The cited author, James Drever, provides an equation expressed in terms of molar equivalents, which means the number of moles of each ion type multiplied by the charge of the ion. For example,1 mole of HCO31− in solution represents 1 molar equivalent, the total charge of a solution always equals zero. On the left-hand side of the equation is the sum of conservative cations minus the sum of conservative anions, balancing this on the right side is the sum of the anions that could be neutralized by added H+ ions minus H+ ions already present, as indicated by the pH. This right side term is called total alkalinity and it is, quoting Drever, formally defined as the equivalent sum of the bases that are titratable with strong acid. The listing of ions shown on the right in Drever was mHCO3− + 2mCO32− + mB4− + mH34− + mHS− + morganic anions + mOH− - mH+, total alkalinity is measured by adding a strong acid until all the anions listed above are converted to uncharged species. The total alkalinity is not affected by temperature, pressure, or pH, though the values of individual constituents are, Drever further notes that in most natural waters, all ions except HCO3− and CO3−2 have low concentrations. Thus carbonate alkalinity, which is equal to mHCO3− + 2mCO3−2 is also equal to the total alkalinity. Alkalinity or AT measures the ability of a solution to neutralize acids to the point of carbonate or bicarbonate. The alkalinity is equal to the sum of the bases in solution. Other common natural components that can contribute to alkalinity include borate, hydroxide, phosphate, silicate, dissolved ammonia, the bases of some organic acids. Solutions produced in a laboratory may contain a virtually limitless number of bases that contribute to alkalinity, Alkalinity is usually given in the unit mEq/L. Commercially, as in the pool industry, alkalinity might also be given in parts per million of equivalent calcium carbonate

39.
Shield volcano
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A shield volcano is a type of volcano usually built almost entirely of fluid lava flows. They are named for their low profile, resembling a warriors shield lying on the ground and this is caused by the highly fluid lava they erupt, which travels farther than lava erupted from stratovolcanoes. This results in the accumulation of broad sheets of lava. The shape of shield volcanoes is due to the low viscosity of their mafic lava, Shield volcanoes are built by effusive eruptions, which flow out in all directions to create a shield like that of a warrior. Shield volcano itself is taken from the German term Schildvulkan, examples of pyroclastic shields include Billy Mitchell volcano in Papua New Guinea and the Purico Complex in Chile, an example of a felsic shield is the Big Obsidian Flow in Oregon. Active shield volcanoes experience near-continuous eruptive activity over long periods of time. Mount Everest, by comparison, is 8,848 m in height, the research has not yet been confirmed. Shield volcanoes feature a slope that gradually steepens with elevation before eventually flattening near the summit. In height they are typically about one twentieth their width, although the general form of a typical shield volcano varies little worldwide regional differences exist in their size and morphological characteristics. 4° and an average volume of 1.7 km3. Rift zones are a prevalent feature on shield volcanoes that is rare on other volcanic types, the large, decentralized shape of Hawaiian volcanoes as compared to their smaller, symmetrical Icelandic cousins can be attributed to rift eruptions. Fissure venting is common in Hawaiʻi, most Hawaiian eruptions begin with a wall of fire along a major fissure line before centralizing to a small number of points. These eruptions, the calmest of volcanic events, are characterized by the emission of highly fluid basaltic lavas with low gaseous content. These lavas travel a far greater distance than those of other types before solidifying, forming extremely wide. Low volumes of such lavas layered over long periods of time are what slowly constructs the characteristically low, central-vent eruptions, meanwhile, often take the form of large lava fountains, which can reach heights of hundreds of meters or more. If eruptive rates are enough, they may even form splatter-fed lava flows. Hawaiian eruptions are often extremely long lived, Puʻu ʻŌʻō, a cone of Kilauea, has been erupting continuously since 1983. These lava flows can be anywhere between 2 and 20 m thick, pāhoehoe flows, in contrast, move in more conventional sheets, or by the advancement of lava toes in snaking lava columns. Increasing viscosity on the part of the lava or shear stress on the part of local topography can morph a pāhoehoe flow into an aa one, although most shield volcanoes are by volume almost entirely Hawaiian and basaltic in origin, they are rarely exclusively so

40.
Planation surface
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In geology and geomorphology a planation surface is a large-scale surface that is almost flat with the possible exception of some residuals hills. The processes that form planation surfaces are labelled collectively planation and are exogenic, planation surfaces are planated regardless of bedrock structures. On Earth they constitute some of the most common landscapes, peneplains and pediplains are types of planation surfaces planated respectively by peneplanation and pediplanation. In addition to there are planation surfaces proposed to be formed by cryoplanation, marine processes, areal glacial erosion. The term planation surface is preferred over others because some more specific planation surface types and processes remain controversial

41.
Ordovician
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The Ordovician is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.2 million years from the end of the Cambrian Period 485.4 million years ago to the start of the Silurian Period 443.8 Mya. Lapworth recognized that the fauna in the disputed strata were different from those of either the Cambrian or the Silurian periods. It received international sanction in 1960, when it was adopted as a period of the Paleozoic Era by the International Geological Congress. Life continued to flourish during the Ordovician as it did in the earlier Cambrian period, invertebrates, namely molluscs and arthropods, dominated the oceans. The Great Ordovician Biodiversification Event considerably increased the diversity of life, fish, the worlds first true vertebrates, continued to evolve, and those with jaws may have first appeared late in the period. Life had yet to diversify on land, about 100 times as many meteorites struck the Earth during the Ordovician compared with today. The Ordovician Period began with a major extinction called the Cambrian–Ordovician extinction event and it lasted for about 42 million years and ended with the Ordovician–Silurian extinction event, about 443.8 Mya which wiped out 60% of marine genera. The dates given are recent radiometric dates and vary slightly from those found in other sources and this second period of the Paleozoic era created abundant fossils that became major petroleum and gas reservoirs. The boundary chosen for the beginning of both the Ordovician Period and the Tremadocian stage is highly significant and it correlates well with the occurrence of widespread graptolite, conodont, and trilobite species. The base of the Tremadocian allows scientists to relate these species not only to each other and this makes it easier to place many more species in time relative to the beginning of the Ordovician Period. A number of terms have been used to subdivide the Ordovician Period. In 2008, the ICS erected an international system of subdivisions. There exist Baltoscandic, British, Siberian, North American, Australian, the Ordovician Period in Britain was traditionally broken into Early, Middle and Late epochs. The corresponding rocks of the Ordovician System are referred to as coming from the Lower, Middle, the Floian corresponds to the lower Arenig, the Arenig continues until the early Darriwilian, subsuming the Dapingian. The Llanvirn occupies the rest of the Darriwilian, and terminates with it at the base of the Late Ordovician. The Sandbian represents the first half of the Caradoc, the Caradoc ends in the mid-Katian, during the Ordovician, the southern continents were collected into Gondwana. Gondwana started the period in equatorial latitudes and, as the period progressed, drifted toward the South Pole, the small continent Avalonia separated from Gondwana and began to move north towards Baltica and Laurentia, opening the Rheic Ocean between Gondwana and Avalonia

42.
Cenozoic
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The Cenozoic Era is the current and most recent of the three Phanerozoic geological eras, following the Mesozoic Era and covering the period from 66 million years ago to the present day. The Cenozoic is also known as the Age of Mammals, because of the mammals that dominated, such as Entelodont, Paraceratherium. The extinction of many large groups such as non-avian dinosaurs, Plesiosauria and Pterosauria allowed the mammals and birds to greatly diversify. Early in the Cenozoic, following the K-Pg event, the planet was dominated by relatively small fauna, including mammals, birds, reptiles. From a geological perspective, it did not take long for mammals, some flightless birds grew larger than humans. These species are referred to as terror birds, and were formidable predators. Mammals came to occupy almost every available niche, and some also grew very large, the Earths climate had begun a drying and cooling trend, culminating in the glaciations of the Pleistocene Epoch, and partially offset by the Paleocene-Eocene Thermal Maximum. The continents also began looking roughly familiar at this time and moved into their current positions. The Cenozoic is divided into three periods, the Paleogene, Neogene, and Quaternary, and seven epochs, the Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, and Holocene. The common use of epochs during the Cenozoic helps paleontologists better organize, there is also more detailed knowledge of this era than any other because of the relatively young, well-preserved rocks associated with it. The Paleogene spans from the extinction of dinosaurs,66 million years ago. It features three epochs, the Paleocene, Eocene and Oligocene, the Paleocene ranged from 66 million to 56 million years ago. The Paleocene is a point between the devastation that is the K-T extinction, to the rich jungles environment that is the Early Eocene. The Early Paleocene saw the recovery of the earth, the continents began to take their modern shape, but all the continents and subcontinent India were separated from each other. Afro-Eurasia was separated by the Tethys Sea, and the Americas were separated by the strait of Panama and this epoch featured a general warming trend, with jungles eventually reaching the poles. The oceans were dominated by sharks as the large reptiles that had once ruled became extinct, archaic mammals filled the world such as creodonts and early primates that evolved during the Mesozoic, and as a result, there was nothing over 10 kilograms. The Eocene Epoch ranged from 56 million years to 33.9 million years ago, in the Early-Eocene, life was small and lived in cramped jungles, much like the Paleocene. There was nothing over the weight of 10 kilograms, among them were early primates, whales and horses along with many other early forms of mammals

43.
Pediplain
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A pediplain is a concept in geology and geomorphology that describe an extensive plain formed by the coalescence of pediments. The processes through which pediplains forms is known as pediplanation, the concepts of pediplain and pediplanation were first developed by geologist Lester Charles King in his 1942 book South African Scenery. The concept gained notoriety as it was juxtaposed to peneplanation, pediplanation is linked to scarp retreat in the following way, as scarps retreat over geological time pediments migrate and extend over large areas. The result is that the surface is eroded chiefly backward and that downward erosion is limited, in contrast to common peneplain conceptualizations several pediplains might form simultaneously at different altitudes and do not necessarily grade to a base level. Pediplains are normally formed in areas of arid and semi-arid climate, cryoplanation is a variant of pediplanation that is restricted to cold climates. Erosion surface Etchplain Paleosurface Planation surface

44.
Geography of Ethiopia
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Ethiopia is located in the Horn of Africa. It is bordered by Eritrea to the north, Djibouti and Somalia to the east, Sudan and South Sudan to the west, and Kenya to the south. Ethiopia has a central plateau that varies from 1,290 to 3,000 m above sea level. Elevation is generally highest just before the point of descent to the Great Rift Valley, a number of rivers cross the plateau, notably the Blue Nile rising from Lake Tana. The plateau gradually slopes to the lowlands of the Sudan on the west, on nearly every side, the walls of the plateaus rise abruptly from the plains, constituting outer mountain chains. The highlands are thus a clearly marked geographic division, in Eritrea, the eastern wall of this plateau runs parallel to the Red Sea from Ras Kasar to Annesley Bay. It then turns due south into Ethiopia and follows closely the line of 40° E for some 600 km, about 9° N there is a break in the wall, through which the Awash River flows eastward. The main range at this point trends southwest, while south of the Awash Valley and this second range sends a chain eastward toward the Gulf of Aden. The southern escarpment of the plateau is irregular, but has a general direction northwest and southeast from 6° N to 3° N. It overlooks the depression in which is Lake Turkana and — east of that lake — the southern Debub Omo Zone, the western wall of the plateau from 6° N to 11° N is well marked and precipitous. North of 11° N the hills turn more to the east, on its northern face the plateau falls in terraces to the level of the eastern Sudan. The eastern escarpment is the best defined of these outer ranges and it has a mean height of 2,100 to 2,400 m, and in many places rises almost perpendicularly from the plain. On surmounting this rocky barrier, the finds that the encircling rampart rises little above the normal level of the plateau. The physical aspect of the highlands is impressive, the northern portion lies mainly between 10° and 15° N. It consists of a mass of Archaean rocks with a mean height of 2,000 to 2,200 m above sea level. Above the plateau rise several irregular and generally ill-defined mountain ranges which attain altitudes of from 3,700 m to just under 4,600 m, many of the mountains are of unusual shape. Characteristic of the country are the enormous fissures which divide it and they are the valleys of the rivers, which rising on the uplands or mountain sides, have cut their way to the surrounding lowlands. One result of the action of the water has been the formation of numerous isolated flat-topped hills or small plateaus, known as ambas, the highest peaks are found in the Semien and Bale ranges

45.
Monsoon
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Usually, the term monsoon is used to refer to the rainy phase of a seasonally changing pattern, although technically there is also a dry phase. The term is sometimes used for locally heavy but short-term rains. The major monsoon systems of the world consist of the West African and Asia-Australian monsoons, the inclusion of the North and South American monsoons with incomplete wind reversal has been debated. The south-west monsoon winds are called Nairutya Maarut in India, the English monsoon came from Portuguese monção, ultimately from Arabic mawsim and/or Hindi mausam, perhaps partly via early modern Dutch monsun. Strengthening of the Asian monsoon has been linked to the uplift of the Tibetan Plateau after the collision of the Indian sub-continent and Asia around 50 million years ago. Because of studies of records from the Arabian Sea and that of the wind-blown dust in the Loess Plateau of China, testing of this hypothesis awaits deep ocean sampling by the Integrated Ocean Drilling Program. The monsoon has varied significantly in strength since this time, largely linked to climate change. A study of marine plankton suggested that the Indian Monsoon strengthened around 5 million years ago, then, during ice periods, the sea level fell and the Indonesian Seaway closed. When this happened, cold waters in the Pacific were impeded from flowing into the Indian Ocean and it is believed that the resulting increase in sea surface temperatures in the Indian Ocean increased the intensity of monsoons. Five episodes during the Quaternary at 2.22 Ma,1.83 Ma,0.68 Ma,0.45 Ma and 0.04 Ma were identified which showed a weakening of Leeuwin Current. The weakening of the LC would have an effect on the sea surface temperature field in the Indian Ocean, thus these five intervals could probably be those of considerable lowering of SST in the Indian Ocean and would have influenced Indian monsoon intensity. The impact of monsoon on the weather is different from place to place. In some places there is just a likelihood of having a more or less rain. In other places, quasi semi-deserts are turned into green grasslands where all sorts of plants. The Indian Monsoon turns large parts of India from a kind of semi-desert into green lands, see photos only taken 3 months apart in the Western Ghats. In places like this it is crucial for farmers to have the right timing for putting the seeds on the fields, Monsoons are large-scale sea breezes which occur when the temperature on land is significantly warmer or cooler than the temperature of the ocean. These temperature imbalances happen because oceans and land absorb heat in different ways, in contrast, dirt, sand, and rocks have lower heat capacities, and they can only transmit heat into the earth by conduction and not by convection. Therefore, bodies of water stay at an even temperature

46.
Equator
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The Equator usually refers to an imaginary line on the Earths surface equidistant from the North Pole and South Pole, dividing the Earth into the Northern Hemisphere and Southern Hemisphere. The Equator is about 40,075 kilometres long, some 78. 7% lies across water and 21. 3% over land, other planets and astronomical bodies have equators similarly defined. Generally, an equator is the intersection of the surface of a sphere with the plane that is perpendicular to the spheres axis of rotation. The latitude of the Earths equator is by definition 0° of arc, the equator is the only line of latitude which is also a great circle — that is, one whose plane passes through the center of the globe. The plane of Earths equator when projected outwards to the celestial sphere defines the celestial equator, in the cycle of Earths seasons, the plane of the equator passes through the Sun twice per year, at the March and September equinoxes. To an observer on the Earth, the Sun appears to travel North or South over the equator at these times, light rays from the center of the Sun are perpendicular to the surface of the Earth at the point of solar noon on the Equator. Locations on the Equator experience the quickest sunrises and sunsets because the sun moves nearly perpendicular to the horizon for most of the year. The Earth bulges slightly at the Equator, the diameter of the Earth is 12,750 kilometres. Because the Earth spins to the east, spacecraft must also launch to the east to take advantage of this Earth-boost of speed, seasons result from the yearly revolution of the Earth around the Sun and the tilt of the Earths axis relative to the plane of revolution. During the year the northern and southern hemispheres are inclined toward or away from the sun according to Earths position in its orbit, the hemisphere inclined toward the sun receives more sunlight and is in summer, while the other hemisphere receives less sun and is in winter. At the equinoxes, the Earths axis is not tilted toward the sun, instead it is perpendicular to the sun meaning that the day is about 12 hours long, as is the night, across the whole of the Earth. Near the Equator there is distinction between summer, winter, autumn, or spring. The temperatures are usually high year-round—with the exception of high mountains in South America, the temperature at the Equator can plummet during rainstorms. In many tropical regions people identify two seasons, the wet season and the dry season, but many places close to the Equator are on the oceans or rainy throughout the year, the seasons can vary depending on elevation and proximity to an ocean. The Equator lies mostly on the three largest oceans, the Pacific Ocean, the Atlantic Ocean, and the Indian Ocean. The highest point on the Equator is at the elevation of 4,690 metres, at 0°0′0″N 77°59′31″W and this is slightly above the snow line, and is the only place on the Equator where snow lies on the ground. At the Equator the snow line is around 1,000 metres lower than on Mount Everest, the Equator traverses the land of 11 countries, it also passes through two island nations, though without making a landfall in either. Starting at the Prime Meridian and heading eastwards, the Equator passes through, Despite its name, however, its island of Annobón is 155 km south of the Equator, and the rest of the country lies to the north

The early modern period of modern history follows the late Middle Ages of the post-classical era. Although the …

Cishou Temple Pagoda, built in 1576: the Chinese believed that building pagodas on certain sites according to geomantic principles brought about auspicious events; merchant-funding for such projects was needed by the late Ming period.

The Ordovician () is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician …

External mold of Ordovician bivalve showing that the original aragonite shell dissolved on the sea floor, leaving a cemented mold for biological encrustation (Waynesville Formation of Franklin County, Indiana).

The Arabian-Nubian Shield (ANS) is an exposure of Precambrian crystalline rocks on the flanks of the Red Sea. The …

Basic dyke cutting granite, Arabian-Nubian Shield

Astronaut photograph (ISS006-E-43186) of the Arabian-Nubian Shield in eastern Sudan, looking NE, with the Red Sea in the background. The N-S structure in the center of the image is the Hamisana Shear Zone. The ANS exposures in eastern Egypt to the north can also be seen, as well as part of the Nile (left) and Arabia (right).